1. Field of the Invention
This invention relates to an electrical device comprising a support rail equipped with a locking end, a part that can be snapped onto the support rail and that includes, in a rear panel, at least one compression spring with an axis orthogonal to the length of the support rail, arranged in a housing which opens onto the locking end of the support rail and offers a stop for the spring.
2. Discussion of the Related Art
Snapping electrical devices onto rails such as standardised sections is well known. The use of helical compression springs that can be applied directly onto the edge of the rail is also known, e.g. according to the document FR-2 551 807. The springs are generally assembled in their housing by inserting them via an opening on the rear of the device by forcing walls of the housing. The fact that the housing remains open at the rear of the device results in a risk of the spring being extracted from its housing, when non-axial strain is applied on the spring. Such non-axial strain is frequently encountered when devices are assembled or disassembled.
The purpose of the invention is to prevent the risk of extraction of the compression springs used in electrical devices to lock them onto support rails such as standardised sections, in a low production cost solution.
According to the invention, the housing opens onto the outside, opposite the rail locking edge, via an opening used for the axial insertion of the spring for its assembly and the housing comprises a spring support bearing surface opposite the stop, this bearing surface being inactive during the insertion of the spring and rendered active after the insertion of the spring.
The bearing surface may be provided either on an elastic housing wall co-operating with a plain helical spring, e.g. by means of a ramped tongue and locking jaw or by means of a locking frame, or on a cavity of the device casing co-operating with a special helical spring, with, in this case, this spring being equipped with a transversal catch set to the locking position by a rotation.